CDC Confirms Higher Blood Lead Levels in Flint Children

CDC continues to recommend that all children under age 6 living in the city of Flint have their blood tested for lead by a health care provider, particularly if they have not had a blood lead test since October 2015.

Jun 25, 2016

The Centers for Disease Control and Prevention on June 24 released the results of its investigation of the potential health impact that lead contamination in the Flint, Mich., water supply had on the blood lead levels of local children and reported that its findings indicate when the source of the water supply was switched to the Flint River, without appropriate corrosion control measures, young children who drank the water had significantly higher blood lead levels than when their water source was the Detroit water system. After the switch back to the Detroit water system, the percentage of children under 6 years with elevated blood lead levels returned to levels seen before the water switch took place, CDC reported.

"This crisis was entirely preventable and a startling reminder of the critical need to eliminate all sources of lead from our children's environment," said Patrick Breysse, Ph.D., director of CDC's National Center for Environmental Health. "CDC is committed to continued support for the people of Flint through our Childhood Lead Poisoning Prevention program and efforts to raise awareness and promote action to address the critical public health issue in communities across the country."

CDC's researchers examined data on levels of lead in blood of children younger than six years before, during, and after the switch in Flint's water source. The current CDC blood lead level of concern (known as a reference level) is 5 or more micrograms of lead per deciliter of blood (≥5 µg/dL), which is based on the population of children ages 1-5 in the United States who are in the top 2.5 percent of children tested for lead in their blood. From April 25, 2014, to Oct. 15, 2015 (the period when the Flint River was used for drinking water), the levels of lead in Flint tap water increased over time and analysis of children’s blood lead data detected an increase in BLLs ≥5 µg/dL. The likelihood that a child consuming the water would have a blood lead level ≥5 µg/dL was nearly 50 percent higher after the switch to Flint River water.

CDC continues to recommend that all children under age 6 living in the city of Flint have their blood tested for lead by a health care provider, particularly if they have not had a blood lead test since October 2015.

CDC noted that its study had limitations: Researchers were not able to account for all factors that might have contributed to a child's exposure to lead, including whether lead-based paint was present in the child's living environment, and the researchers did not have information on the amount of lead in or the amount of water consumed by the tested children, limiting the analysis to evaluation of changes in blood lead levels over time as the source water changed.